Compression regulator



May 13, 1941.

C. L. EVANS COMPRESSION REGULATOR Filed Feb. 9, 1940 2 Sheets-Sheet l CCZJ JvaIZs 76 Z, INVENTOR.

ATTORNEYS.

y c. L. EVANS COMPRESSION REGULATOR Filed Feb. 9, 1940 2 Sheets-Sheet 2 dhZQfivarw IN VEN TOR.

ATTORNEYS.

Patented May 13, 1941 UNITED STATES 2 Claims.

This invention [aims to provide novel means for shifting the pistons of an internal combustion engine, in the cylinders, to regulate compression under conditions wherein such a regulation is desirable or necessary.

It is within the province of the disclosure to improve generally and to enhance the utility of devices of that type to which the present invention appertains.

With the above and other objects in view, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

In the drawings:

Fig. 1 shows, in side elevation, a portion of an internal combustion engine wherein the present improvements have been embodied;

Fig. 2 is a longitudinal section of the device depicted in Fig. 1;

Fig. 3 is a transverse section of the device shown in Figs. 1 and 2, the cutting plane of Fig. 3 being indicated in Fig. 2;

Fig. 4 is an elevation wherein parts are sectioned and broken away.

The device is shown adapted to an internal combustion engine wherein the cylinders are disposed nadially.

The numeral 29 designates a portion of a crank case, having an outwardly projecting sleeve 2|, wherein is secured a race 22, receiving anti-friction balls 23.

The drive shaft of an internal combustion engine is marked as a whole by the numeral 24. The drive shaft 24 includes a solid section 25, and a tubular section 26, which is mounted for rotation in the bearing structure 2223. The crank element of the section 23 is designated by the numeral 21, and the crank element of the section 26 is denoted by the numeral 39. The crank element 21 carries a Wrist pin 28, secured at 29 in the crank element 30.

An eccentric 3| is mounted for rotary adjustment on the wrist pin 28, a gear wheel 32 being connected to the eccentric 3|, to turn therewith on the wrist pin 28. The gear wheel 32 meshes with a gear wheel 33, secured to one end of an auxiliary shaft 34, mounted concentrically in the crank shaft section 26, to turn in said section, the shaft being held against longitudinal movement therein.

A cylinder 35 is bolted to the crank case 20 and, at one end, the cylinder has an inlet 36 for liquid supplied under pressure, which may be furnished by a force pump and auxiliary mechanism not germane to the present invention. A piston 31 is mounted for reciprocation in the cylinder 35. A pressure chamber 38 exists in the cylinder 35, between the piston 31 and the inlet 36. A resilient annular packing 39 is connected to the piston 31 and to the cylinder 35, and prevents leakage past the piston.

The piston 31 has a cuff 49, defining a shoulder 4| in the piston. A compression spring 42 surrounds the cuif 43 of the piston 31, one end of the spring abutting against the shoulder 4|, the opposite end of the spring abutting against the crank case 23. The cuff 43 of the piston 31 is splined at 43 to the fixed sleeve 2|, for right line movement therealong.

A shaft 44 extends into the piston 31, and is held in the piston, ro'tatably, but against right line movement, by an anti-friction bearing 45, assembled with the piston. The shaft 44 is splined at 46 into the crank shaft section 26, for right line movement with respect thereto. The shaft 44 has a cavity,-wherein are located quick spiral ribs 41, cooperating with spiral grooves 48 in the auxiliary shaft 34.

A master connecting rod 49 is mounted to swing on the eccentric sleeve 3|, any desired number of auxiliary connecting rods 53 being pivoted at 5| to the master connecting rod 49. The piston rods 49 and 50 of course are connected to the pistons of an internal combustion engine, although the pistons are not depicted in the drawmgs.

In practical operation, when pressure enters the chamber 38 by way of the inlet 36, the piston 31 is advanced, the spring 42 being compressed. When the piston 31 is advanced, the shaft 44 is advanced, and the spiral ribs 41 on the shaft 44, cooperating with the spiral grooves 48 of the shaft 34, impart rotation to the shaft 34 and to the gear wheel 33. From the gear wheel 33, rotary adjustment is imparted to the eccentric 3|, by way of the pinion 32, the piston rods 49 and 53 being advanced or retracted at the will of an operator, to regulate the compression in the engine cylinders.

Having thus described the invention, what is claimed is:

1. In a compression regulator for internal combustion engines, a shaft having a crank, an eccentric journaled on the crank, a piston rod pivotally mounted on the eccentric, an auxiliary shaft journaled in the crank shaft, a gear connection between the eccentric and the auxiliary shaft, and mechanism under the control of an operator for rotating the auxiliary shaft, to shift the position, of the piston rod and regulate compression, said mechanism embodying a cylinder, a piston sildable in the cylinder and. subject to fluid pressure, and a third shaft mounted to rotate in the piston and held against longitudinal movement therein, the third shaft having threaded connection with the auxiliary shaft.

2. In a compression regulator for internal combustion engines, a shaft having a crank, an eccentric journaled on the crank, a piston rod pivotally mounted on the eccentric, an auxiliary shaft journaled in the crank shaft, a gear connection between the eccentric and the auxiliary shaft, and mechanism under the control of an operator for rotating the auxiliary shaft, to shift the position of the piston rod and regulate compression, said mechanism embodying a cylinder, a piston slidable in the cylinder and subject to fluid pressure, a flexible packing connected to the periphery of the piston and to the cylinder, a return spring in the cylinder and coaoting with the cylinder and the piston, a third shaft mounted for rotation in the piston and held against longitudinal movement therein, and a threaded connection between the third shaft and the auxiliary shaft.

CARROLL L. EVANS. 

